Compounds for neutron radiation detectors and systems thereof

Abstract

A material according to one embodiment exhibits an optical response signature for neutrons that is different than an optical response signature for gamma rays, said material exhibiting performance comparable to or superior to stilbene in terms of distinguishing neutrons from gamma rays, wherein the material is not stilbene, the material comprising a molecule selected from a group consisting of: two or more benzene rings, one or more benzene rings with a carboxylic acid group, one or more benzene rings with at least one double bound adjacent to said benzene ring, and one or more benzene rings for which at least one atom in the benzene ring is not carbon.

What is claimed is: 
     
       1. A material exhibiting an optical response signature for neutrons that is different than an optical response signature for gamma rays, said material exhibiting performance comparable to or superior to stilbene in terms of distinguishing neutrons from gamma rays, wherein the material is not stilbene, the material comprising a molecular motif selected from a group consisting of:
 two or more benzene rings, 
 one or more benzene rings with a carboxylic acid group, 
 one or more benzene rings with at least one double bond adjacent to at least one of the one or more benzene rings, and 
 one or more six-member rings comprising:
 carbon atoms; and 
 at least one non-carbon atom, 
 wherein each atom in each six-member ring is double-bonded to one other atom in the six-member ring, and 
 
 wherein the material is in the form of a crystal having physical characteristics of formation from solution, the physical characteristics including faceted growth on at least one face of the crystal. 
 
     
     
       2. The material of  claim 1 , wherein at least about 95 mol % of the crystal is the material. 
     
     
       3. The material of  claim 1 , wherein the crystal has a length of greater than 1 mm in one dimension. 
     
     
       4. The material of  claim 1 , wherein the material is in the form of a crystal, wherein the crystal has a length of less than 1 mm in one dimension. 
     
     
       5. The material of  claim 1 , wherein the crystal has a length of greater than 5 mm in one dimension. 
     
     
       6. The material of  claim 1 , wherein the material includes a molecule having two or more phenyl groups and continuous conjugation throughout the molecule. 
     
     
       7. The material of  claim 1 , wherein the material is selected from a group consisting of:
 1-1-4-4-tetraphenyl-1-3-butadiene; 
 2-fluorobiphenyl-4-carboxylic acid; 
 4-biphenylcarboxylic acid; 
 9-10-diphenylanthracene; 
 9-phenyl anthracene; 
 1-3-5-triphenylbenzene; 
 m-terphenyl; 
 bis-MSB; 
 diphenylacetylene; 
 2-5-diphenyoxazole; 
 4-benzylbiphenyl; 
 biphenyl; 
 4-methoxybiphenyl; 
 n-phenylanthranilic acid; and 
 1-4-diphenyl-1-3-butadiene. 
 
     
     
       8. The material of  claim 1 , the physical characteristics including faceted growth on at least two faces of the crystal. 
     
     
       9. A system, comprising:
 the material of  claim 1 ; and 
 a photodetector for detecting the response of the material to neutron and gamma ray irradiation. 
 
     
     
       10. The system of  claim 9 , further comprising a processor for performing a discrimination method for processing an output of the photodetector using pulse shape discrimination for differentiating responses of the material to the neutron and gamma ray irradiation. 
     
     
       11. The system of  claim 10 , further comprising a display device for outputting a result of the processing. 
     
     
       12. A method, comprising:
 growing an organic crystal from solution, the organic crystal exhibiting an optical response signature for neutrons that is different than an optical response signature for gamma rays, said organic crystal exhibiting performance comparable to or superior to stilbene in terms of distinguishing neutrons from gamma rays, wherein the material is not stilbene. 
 
     
     
       13. The method of  claim 12 , wherein the crystal comprises a material selected from a group consisting of:
 1-1-4-4-tetraphenyl-1-3-butadiene; 
 2-fluorobiphenyl-4-carboxylic acid; 
 4-biphenylcarboxylic acid; 
 9-10-diphenylanthracene; 
 9-phenylanthracene; 
 1-3-5-triphenylbenzene; 
 m-terphenyl; 
 bis-MSB; 
 diphenylacetylene; 
 2-5-diphenyoxazole; 
 4-benzylbiphenyl; 
 biphenyl; 
 4-methoxybiphenyl; 
 n-phenylanthranilic acid; and 
 1-4-diphenyl-1-3-butadiene. 
 
     
     
       14. The method of  claim 12 , the crystal comprising a molecular motif selected from a group consisting of:
 two or more benzene rings, 
 one or more benzene rings with a carboxylic acid group, 
 one or more benzene rings with at least one double bond adjacent to at least one of the one or more benzene rings, and 
 one or more six-member rings comprising:
 carbon atoms; and 
 at least one non-carbon atom, 
 wherein each atom in each six-member ring is double-bonded to one other atom in the six-member ring. 
 
 
     
     
       15. The method of  claim 12 , wherein the crystal has a length of greater than 1 mm in one dimension. 
     
     
       16. The method of  claim 12 , wherein the crystal has a length of greater than 5 mm in one dimension. 
     
     
       17. The method of  claim 12 , wherein the crystal has a length of greater than 25 mm in one dimension. 
     
     
       18. The method of  claim 12 , said solution being comprised of a solvent and a solute, said solvent comprising more than 30% of said solution, and said solution being held at a temperature that is less than that of the melting point of said solute during the growing.